Lesson 17 - Crocodylians

Question 1

crocodile locomotion

Answer 1

• Laternal angulation of the tail to swim
  —–Hind legs help
  -Galloping of australian freshwater
  -High walking
  -Belly crawl

Question 2

phytosaurs

Answer 2

• Are extinct
• Look very similar to the crocodylains
• Nostrils are just anterior to the eyes
• On crocodylians → nostrils are on the tip of nose
• Phytosaurs lack a secondary palate (crocodylians have this)
• Herbivert has evolved independently

Question 3

enormous alligators in the late crustation

Answer 3

about 12 m long

Question 4

secondary palate

Answer 4

– Air can be drawn in through the external nostril and bypass the oral canal ( humans can do this to)
– Allosw the animal to breathe and manipulate prey as well
—-Adds strength and robustness to this part of the skull

Question 5

has a 4 chambered heart

Answer 5

• Unlike turtles and squamates
• Enables to avoid the mixing of oxygenated and
  deoxygenated blood

Question 6

Crocodiles have faint detectors for detecting faint vibrations

Answer 6

• Important for prey detection
• Can detect the tiniest ripple in the water
• —-Helps for detecting prey

Question 7

Crocodylia have PARENTAL CARE

Answer 7

Males help as well
– Baby crocs form a cresh → group of unrelated crocs and form social groups
— Allomaternal care → some dads were seen carrying creshs that weren’t all his own